For me, the concept of ‘sleep hygiene’ is a misnomer and somehow doesn’t fit with the idea of a good night's sleep; it sounds too specific, too clinical.
Sleep is such a sensory experience, and different people prefer different environments.
There are no hard and fast rules about what makes a room conducive to sleep other than that the room should be dark, cool, comfy and quiet.
Clinically the definition of sleep hygiene is “a set of general recommendations about lifestyle (e.g. diet, exercise, substance use) and environmental factors (e.g. light noise, temperature) that may promote or interfere with sleep”. Sleep hygiene may include some education about what constitutes “normal” sleep and changes in sleep patterns that occur with ageing.
In other words, make your room into a room that you love so that it is enticing and relaxing. Think about the timing of food intake, exercise intensity and any other substance you might consume, such as caffeine, alcohol etc. A relaxed mind and a relaxed body in a room conducive to sleep = a great night's sleep.